I'm using a Motorola Moto G4 Play with LineageOS. From time to time I get a message that someone tried to call me, but I wasn't available. This hasn't happened with other phones, so I suspect that it is some bug/bad behaviour.
From what I can tell this usually happens when the phone is locked. However at least once it happened when I was using the phone. The phone itself is not in "Do not disturb" mode. But I try to disable it (although it is disabled) my impression is that phone calls come through. As far as I can tell the phone always has radio reception. So I'm out of ideas what can cause this behaviour.
How can I debug this behaviour or do know what can cause this behaviour?